The invention relates to a low voltage multipole circuit breaker with double housing, each pole of which comprises a single-pole breaking unit having a parallelepipedic box made of molded plastic material and having two large side faces, and contacts associated with an extinguishing chamber housed in the unit, wherein several units are mounted side by side in a molded case to form the multipole circuit breaker.
A circuit breaker of the kind mentioned comprises for each pole an individual unit formed by a box made of molded plastic material containing the contacts and extinguishing chambers. The advantages of modular systems of this kind are well-known, in particular the reductions in manufacturing and assembly costs. They do however impose constraints as to the respective positioning of the different modules, namely involving the connection between the movable parts of the different single-pole units. A state-of-the-art circuit breaker comprises a rotating shaft which passes through all the single-pole units to drive all movable contacts in rotation simultaneously. The presence of this rotating shaft imposes constraints of positioning and architecture.